Organic light-emitting element including a conductive pattern which passes through an organic material layer to connect to an external terminal of a second electrode

ABSTRACT

The present invention relates to an organic light-emitting element and a production method thereof. Specifically, the present invention relates to an organic light-emitting element, which has excellent productivity during mass production thereof and may allow simplification of vapor deposition equipment, and the like, and a production method thereof.

This application is a national stage application of PCT/KR2011/005945,filed Aug. 12, 2011, which claims priority to and the benefit of KoreanPatent Application No. 10-2010-0078193, filed in the Korean IntellectualProperty Office on Aug. 13, 2010, and Korean Patent Application No.10-2010-0078904, filed in the Korean Intellectual Property Office onAug. 16, 2010, the entire contents of which are incorporated herein byreference.

TECHNICAL FIELD

The present invention relates to an organic light-emitting element and aproduction method thereof. Specifically, the present invention relatesto an organic light-emitting element, which has excellent productivityfor mass production thereof and may allow simplification of vapordeposition equipment and the like, and a production method thereof.

BACKGROUND ART

An organic light-emitting element is composed of two opposing electrodesand organic material thin films of a plurality of layers havingsemiconductor-like properties interposed therebetween. The organiclight-emitting element having the configuration uses a phenomenon inwhich electric energy is converted into light energy by using an organicmaterial, that is, an organic light emission phenomenon. Specifically,when voltage is applied between two electrodes in a structure in whichan organic material layer is disposed between an anode and an electrode,holes from the anode and electrons from the cathode are injected intothe organic material layer. When the injected holes and electrons meeteach other, an exciton is formed, and the exciton falls down to a bottomstate to emit light.

In the aforementioned organic light-emitting element, light generatedfrom the organic material layer is emitted through a light transmissiveelectrode, and the organic light-emitting element may be typicallyclassified into a top emission type, a bottom emission type, and adouble-sided emission type. In the case of the top emission or bottomemission type, one of two electrodes needs to be a light transmissiveelectrode, and in the case of the double-sided emission type, both thetwo electrodes needs to be a light transmissive electrode.

In respect to the aforementioned organic light-emitting element, manystudies have been conducted since Kodak Co., Ltd. announced that when amultilayer structure is used, the element may be driven at a lowvoltage, and recently, a natural color display using an organiclight-emitting element is attached to a mobile phone and commercialized.

Further, as recent studies on the organic light-emitting element using aphosphorescent material instead of a fluorescent material in the relatedart have been conducted, efficiency has been rapidly improved, and it isalso expected that the element would be able to replace an illuminationin the related art in the near future.

In order to use the organic light-emitting element as illumination, theelement needs to be driven with high brightness unlike the natural colordisplay in the related art, and a constant brightness needs to bemaintained like the illumination in the related art. In order tosufficiently improve the brightness of the organic light-emittingelement, light emission needs to be implemented in a large area, and inorder to implement light emission in the large area, a high drivingcurrent needs to be used. In addition, in order to maintain constantbrightness in the large area, the aforementioned high current needs tobe uniformly injected into the element having the large area.

In general, an organic light-emitting element for illumination has astructure in which a transparent electrode, an organic material layer,and a metal electrode are sequentially deposited on a substrate. Whenthe organic light-emitting element is produced, the organic materiallayer and the deposition pattern of the metal electrode have differentareas on a plan view, and thus different masks are used when the organicmaterial layer and the metal electrode are deposited. Accordingly, thereare problems in that it is necessary to replace the mask during thedeposition process, productivity is not high due to complex vapordeposition equipment, and production costs are also high.

Currently, a generally-used cluster type deposition apparatus includes amask for an organic material layer or a mask for a metal electrode perdeposition chamber, and when a substrate is introduced into thedeposition chamber, the mask and the substrate are combined and then anorganic material or metal is deposited thereon. In the process, thenumber of masks only increases proportionally to the number ofdeposition chambers. In such a mode, a time for transferring thesubstrate, a time for combining the substrate and the mask, a time fordepositing the organic material or metal and the like, are required, andthus there is a limitation on improving productivity.

On the contrary, in the case of in-line vapor deposition equipment, mostof the preparation processes may be omitted, and thus an opportunity toimprove productivity is inevitable. However, there is a problem in thateven the in-line vapor deposition equipment needs the number of masksthat is equal to or more than the number of all the substrates that areinputted into the deposition chamber and on which deposition isperformed. When an organic material deposition pattern and an inorganicmaterial deposition pattern are different from each other, the number ofmasks required needs to be double or more the number of substrates.Furthermore, while the organic material deposition process is changedinto the metal electrode deposition process during the in-line process,a mask replacement process is needed, and productivity may be reducedduring the procedure.

In order to implement mass production of an organic light-emittingelement for illumination in the future, there is a need for a study thatmay increase productivity of an organic light-emitting element without amask replacement process in the in-line vapor deposition equipment.

DETAILED DESCRIPTION OF THE INVENTION Technical Problem

The present invention has been made in an effort to provide an organiclight-emitting element, which has excellent productivity and may beproduced by allowing simplification of vapor deposition equipment, and aproduction method thereof. In particular, the present invention has beenmade in an effort to provide an organic light-emitting element, whichmay increase productivity by decreasing the number of masks required inthe in-line process to omit the mask replacement process during thedeposition process and may reduce production costs, and a productionmethod thereof.

Technical Solution

An exemplary embodiment of the present invention provides an organiclight-emitting element having a structure in which a first electrode, anorganic material layer, and a second electrode are sequentially stackedon a substrate, in which a shape of the second electrode is the same asthat of the organic material layer.

Another exemplary embodiment of the present invention provides anorganic light-emitting element having a structure in which a firstelectrode, an organic material layer, and a second electrode aresequentially stacked on a substrate, in which an external terminal ofthe second electrode is provided to be insulated from the firstelectrode on the substrate, and a conductive pattern that electricallyconnects the second electrode with the external terminal of the secondelectrode is provided.

Yet another exemplary embodiment of the present invention provides amethod for producing an organic light-emitting element, including:forming a first electrode on a substrate; forming an organic materiallayer on the first electrode by using a mask; and forming a secondelectrode on the organic material layer, in which the organic materiallayer and the second electrode are formed by using the same mask.

Advantageous Effects

In the organic light-emitting element according to the presentinvention, the shapes of the pattern of the organic material layer andthe pattern of the second electrode are same as each other, and thus thesame mask may be used without a need to replace the mask when theorganic material layer and the second electrode are each formed, andaccordingly, productivity of the organic light-emitting element may beincreased and production costs may be reduced. Further, when the organiclight-emitting element is produced, it is possible to allowsimplification of vapor deposition equipment, thereby obtaining aneffect of reducing investment costs.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a view illustrating a specific example of an organiclight-emitting element in the related art.

FIG. 2 is a view illustrating a specific example of an organiclight-emitting element according to the present invention.

FIG. 3 is a view comparing the flow of electric current in the specificexample of the organic light-emitting element in the related art withthat in the specific example of the organic light-emitting elementaccording to the present invention.

FIGS. 4 and 5 are views illustrating a specific example of various formsof a conductive pattern in the organic light-emitting element accordingto the present invention.

FIG. 6 is a view illustrating a specific example of an angle between theconductive pattern and an external terminal plane of a second electrodein the organic light-emitting element according to the presentinvention.

FIGS. 7 to 10 are views illustrating a process of forming an organicmaterial layer and an upper electrode with one mask according to thepresent invention.

BEST MODE

Hereinafter, the present invention will be described in detail.

An organic light-emitting element according to an exemplary embodimentof the present invention is an organic light-emitting element having astructure in which a first electrode, an organic material layer, and asecond electrode are sequentially stacked on a substrate, in which ashape of the second electrode is the same as that of the organicmaterial layer.

In the present specification, the fact that the shape of the secondelectrode is the same as that of the organic material layer means thatthe area of the second electrode is the same as that of the organicmaterial layer or has a size difference from that of the organicmaterial layer in a range within 10%, or that the pattern form of thesecond electrode is the same as that of the organic material layer.

The present invention has a configuration in which the shape of thesecond electrode is the same as that of the organic material layer, andthus the same mask may be used as a mask for forming the organicmaterial layer and a mask for forming the second electrode.

In the present specification, the area of the organic material layerrefers to an area that the organic material layer occupies on the firstelectrode when the organic material layer is formed on the firstelectrode, that is, an area when viewed from the top surface side of thesecond electrode of the element. In addition, the area of the secondelectrode similarly refers to an area that the second electrode coversthe first electrode and the organic material layer, that is, an areawhen viewed from the top surface side of the second electrode of theelement.

In the present specification, the pattern form of the organic materiallayer refers to a shape that the organic material layer is stacked onthe first electrode when the organic material layer is formed on thefirst electrode, that is, a pattern form when viewed from the topsurface side of the second electrode of the element. Furthermore, thepattern form of the second electrode similarly refers to a pattern formthat the second electrode covers the first electrode and the organicmaterial layer, that is, a pattern form when viewed from the top surfaceside of the second electrode of the element.

In the present invention, when the same mask is used as the mask forforming the organic material layer and the mask for forming the secondelectrode, the area of the second electrode and that of the organicmaterial layer may be the same as each other, but may have a slightdifference caused by a forming method, an error in process or the like.However, the same mask is used, and thus the size difference of the areamay be in a range within 10%, preferably 5%, and more preferably 3%.

In the present invention, when the same mask is used as the mask forforming the organic material layer and the mask for forming the secondelectrode, the pattern shapes are the same as each other when the secondelectrode and the organic material layer are viewed from the top surfaceside, but as described above, the areas of the second electrode and theorganic material layer may be slightly different from each other due toa forming method, an error in process or the like, and thus the aspectratios of the pattern forms of the second electrode and the organicmaterial layer may be increased or decreased as proportionally to eachother.

In the present invention, when the same mask is used, the organicmaterial layer and the second electrode have the same shape and the samearea or a difference in areas within a specific range, and are formed inregions that correspond to each other.

In the present invention, the organic light-emitting element may includean external terminal of the second electrode provided to be insulatedfrom the first electrode on the substrate, and a conductive pattern thatelectrically connects the second electrode with the external terminal ofthe second electrode.

The external terminal of the second electrode is electrically connectedto the second electrode to receive an external voltage. In the presentinvention, the second electrode and the external terminal of the secondelectrode may be electrically connected to each other by including theconductive pattern that electrically connects the external terminal ofthe second electrode with the second electrode.

In order for the organic light-emitting element to emit light, anexternal voltage needs to be applied on the first electrode and thesecond electrode. The external voltage may be supplied directly to thefirst electrode, but the second electrode is electrically connected to aseparate external terminal, and then an external voltage is supplied tothe separate external terminal.

For electrical connection of the second electrode with the externalterminal of the second electrode in the related art, the secondelectrode is configured to be brought into direct contact with theexternal terminal of the second electrode, as illustrated in FIG. 3.However, in the case of the configuration, there are problems in thatthe production process is complex and high costs are required. However,in the present invention, as described above, the electrical connectionof the second electrode with the external terminal of the secondelectrode may be supplemented by the aforementioned conductive patternwhile allowing the shape of the organic material layer to be the same asthat of the second electrode.

The conductive pattern may have a structure in which the conductivepattern passes through the organic material layer from the top surfaceof the external terminal of the second electrode to be brought intocontact with the second electrode or pass through the second electrode.

Specifically, the organic light-emitting element according to thepresent invention may include: a substrate; a first electrode providedon the substrate; an external terminal of a second electrode provided tobe insulated from the first electrode; an organic material layerprovided so as to cover at least a portion of the first electrode andthe external terminal of the second electrode; the second electrodeprovided on the organic material layer and having the same shape as thatof the organic material layer; and a conductive pattern having astructure in which the conductive pattern passes through the organicmaterial layer from the top surface of the external terminal of thesecond electrode to be brought into contact with the second electrode orpass through the second electrode.

In the present invention, for insulation of the first electrode disposedon the substrate from the external terminal of the second electrode, aninsulating layer may be provided. The insulating layer is notparticularly limited in the material or structure thereof as long as thelayer may insulate the first electrode from the external terminal of thesecond electrode. When the insulating layer is provided, the organicmaterial layer may be provided so as to cover the insulating layer. Theinsulating layer may be formed of at least one oxide selected from ageneral photoresist material; polyimide; polyacryl; silicon nitride;silicon oxide; aluminum oxide; aluminum nitride; alkali metal; orfluoride of alkaline earth metal.

An organic light-emitting element according to another exemplaryembodiment of the present invention has a structure in which a firstelectrode, an organic material layer, and a second electrode aresequentially stacked on a substrate, in which an external terminal ofthe second electrode is provided to be insulated from the firstelectrode on the substrate, and a conductive pattern that electricallyconnects the second electrode with the external terminal of the secondelectrode is provided. The explanation on the external terminal of thesecond electrode and the conductive pattern is described as above.

In the present invention, an insulating layer may be additionallyprovided on at least a portion of the outermost part of a region inwhich the organic material layer is brought into contact with the firstelectrode. In the present invention, it is unlikely that the firstelectrode and the second electrode are electrically connected so as tocause a short, but it is further unlikely that the two electrodes areelectrically connected by providing an insulating layer therebetween.The insulating layer may be formed of at least one oxide selected from ageneral photoresist material; polyimide; polyacryl; silicon nitride;silicon oxide; aluminum oxide; aluminum nitride; alkali metal; orfluoride of alkaline earth metal. The thickness of the insulating layermay be from 10 nm to 10 μm, but is not limited thereto.

A specific example of an organic light-emitting element in the relatedart is illustrated in FIG. 1.

As illustrated in FIG. 1, the organic light-emitting element in therelated art includes a first electrode provided on a substrate, anorganic material layer, and a second electrode, and the second electrodeis brought into direct contact with an external electrode of the secondelectrode, and thus an external voltage is supplied thereto. That is, inthe organic light-emitting element in the related art, the surface ofthe external terminal of the second electrode needs to be brought intodirect contact with the second electrode, so that the second electrodeand the external terminal of the second electrode are electricallyconnected to each other. In other words, an organic material layer neednot be deposited at a position corresponding to the external terminal ofthe second electrode. As a result, the sizes of areas of the organicmaterial layer and the deposition pattern of the second electrode on aplan view are inevitably different from each other.

Meanwhile, a specific example of the organic light-emitting elementaccording to the present invention is illustrated in FIG. 2.

As illustrated in FIG. 2, the organic light-emitting element accordingto the present invention includes a first electrode on a substrate, anorganic material layer, and a second electrode, in which the areas ofthe organic material layer and the pattern of the second electrode arethe same as each other. In the organic light-emitting element accordingto the present invention, the second electrode may be electricallyconnected with the external terminal of the second electrode through aconductive pattern formed on the external terminal of the secondelectrode, even though the deposition areas of the organic materiallayer and the second electrode layer are the same as each other.

The conductive pattern may be formed before an organic material layer isformed on the top surface of the external terminal of the secondelectrode. The conductive pattern may be formed in a region, in whichthe second electrode is to be formed, on the top surface of the externalterminal of the second electrode before the organic material layer andthe second electrode are formed.

When viewed from the top surface side of the substrate, various formsare possible as the conductive pattern. As explained above, in a regionin which the conductive pattern is to be formed, the conductive patternmay be made as one figure form, and may be distributed as a form of aplurality of independent or interconnected points. The transverse crosssectional shape of the conductive pattern is not particularly limited,and may be any shape, such as a triangular shape, a square shape, anamorphous shape and the like. Further, the side surface shape of theconductive pattern may be a square shape or a rectangular shape, but mayhave a lozenge-shape, a triangular shape or other modified shapes.Various shapes of the conductive pattern are illustrated in FIGS. 4 and5.

In the side surface shape of the conductive pattern, the maximum angleof the conductive pattern with the top surface of the external terminalof the second electrode is very important. The maximum angle ispreferably 40° or more. Even when the organic material layer is formed,the organic material is exposed without covering all the side surface ofthe conductive pattern, and then when the second electrode is formed,the conductive pattern may be electrically connected with the secondelectrode. A specific example thereof is illustrated in FIG. 6.

In addition, it is preferred that the height of the conductive patternis twice or more than the thickness of the organic material layer. Whenthe conductive pattern includes two or more patterns, it is preferredthat the height of the conductive pattern is twice or more than thethickness of the organic material layer based on the lower height. It ispreferred that the height of the conductive pattern is, for example, 1micrometer or more.

The higher electrical conductivity of the conductive pattern, thebetter. It is preferred that electrical conductivity is, for example,1×10⁻⁴ S/m or more.

As a method for forming the conductive pattern, it is also possible toperform etching or use a printing method after a conductive materiallayer is formed through deposition and the like.

A metal such as aluminum, chromium, copper, silver, gold, molybdenum andthe like, or a transparent conductive material such as indium tin oxide(ITO), indium zinc oxide (IZO) and the like, which may be generallydeposited, may be pattern deposited by using a mask, or a pattern may beformed by performing deposition on the entire region and then performingpartial etching. Furthermore, it is also possible to perform printing byperforming patterning with a conductive paste or ink, which includessilver, copper, carbon and the like.

Further, FIG. 3 illustrates comparison of the flow of electric currentin a specific example of the organic light-emitting element in therelated art with that in a specific example of the organiclight-emitting element according to the present invention.

As described above, in the organic light-emitting element according tothe present invention, the organic material layer and the secondelectrode have the same shape, and thus it is not necessary to replacethe mask in the process of forming each of the organic material layerand the second electrode, thereby increasing the productivity of theorganic light-emitting element. In addition, when the organiclight-emitting element is produced, it is possible to allowsimplification of vapor deposition equipment, thereby obtaining aneffect of reducing investment costs.

In the organic light-emitting element according to the presentinvention, the first electrode and the second electrode may be an anodeand a cathode, respectively, and may also be a cathode and an anode,respectively. As materials for the first electrode and the secondelectrode, those known in the art may be used, and the same material mayalso be used. As materials for the first electrode and the secondelectrode, a metal, a transparent conductive oxide, a conductive polymeror a composite thereof, or a stacked structure may be used.

For example, the first electrode may be a transparent electrode and thesecond electrode may be a metal electrode, but the electrodes are notlimited thereto. Specifically, the first electrode may be formed bydepositing ITO and the like, and the second electrode may be formed bydepositing Al and the like.

For example, the electrode may be formed of one or more selected frommagnesium, calcium, sodium, potassium, titanium, indium, yttrium,lithium, gadolinium, aluminum, platinum, gold, tungsten, tantalum,copper, silver, tin, and lead.

In addition, the first electrode may also be formed of a transparentconductive oxide. Here, the transparent conductive oxide may be at leastone oxide selected from indium (In), tin (Sn), zinc (Zn), gallium (Ga),cerium (Ce), cadmium (Cd), magnesium (Mg), beryllium (Be), silver (Ag),molybdenum (Mo), vanadium (V), copper (Cu), iridium (Ir), rhodium (Rh),ruthenium (Ru), tungsten (W), cobalt (Co), nickel (Ni), manganese (Mn),aluminum (Al), and lanthanum (La).

The first electrode may be formed by using any one physical vapordeposition (PVD) selected from sputtering, e-beam evaporation, thermalevaporation, laser molecular beam epitaxy (L-MBE), and pulsed laserdeposition (PLD); any one chemical vapor deposition selected fromthermal chemical vapor deposition, plasma-enhanced chemical vapordeposition (PECVD), light chemical vapor deposition, laser chemicalvapor deposition, metal-organic chemical vapor deposition (MOCVD), andhydride vapor phase epitaxy (HVPE); or atomic layer deposition (ALD).

For example, a material for the second electrode may be a transparentconductive oxide. The transparent conductive oxide may be at least oneoxide selected from indium (In), tin (Sn), zinc (Zn), gallium (Ga),cerium (Ce), cadmium (Cd), magnesium (Mg), beryllium (Be), silver (Ag),molybdenum (Mo), vanadium (V), copper (Cu), iridium (Ir), rhodium (Rh),ruthenium (Ru), tungsten (W), cobalt (Co), nickel (Ni), manganese (Mn),aluminum (Al), and lanthanum (La). Among them, it is preferred that thefilm is formed of indium tin oxide (ITO) or indium zinc oxide (IZO).

Furthermore, a material for the second electrode may be one or moreselected from magnesium, calcium, sodium, potassium, titanium, indium,yttrium, lithium, gadolinium, aluminum, silver, platinum, gold,tungsten, tantalum, copper, tin, and lead.

The second electrode may be formed by using any one physical vapordeposition (PVD) selected from sputtering, e-beam evaporation, thermalevaporation, laser molecular beam epitaxy (L-MBE), and pulsed laserdeposition (PLD); any one chemical vapor deposition selected fromthermal chemical vapor deposition, plasma-enhanced chemical vapordeposition (PECVD), light chemical vapor deposition, laser chemicalvapor deposition, metal-organic chemical vapor deposition (MOCVD), andhydride vapor phase epitaxy (HVPE); or atomic layer deposition (ALD).

The thickness of the second cathode may be from 50 nm to 5 μm, but isnot limited thereto.

In the present invention, the external terminal of the second electrodemay be formed of a conductive material, and may be formed of the samematerial as that of the first electrode or the second electrode.

A metal auxiliary electrode may be formed on the first electrode inorder to reduce a sheet resistance value. The metal auxiliary electrodemay be formed by using a material and a method known in the art. Forexample, the metal auxiliary electrode may be formed by aphotolithography method using Cr, Mo, Cu, Al and the like.

For example, the organic light-emitting element according to the presentinvention may be produced by depositing a metal or a metal oxide havingconductivity, or an alloy thereof on a substrate to form an anode, byusing a physical vapor deposition (PVD) method such as sputtering ore-beam evaporation, forming an organic material layer thereon, and thendepositing a material, which may be used as the cathode, thereon. Inaddition to the aforementioned methods, in order to manufacture anorganic light-emitting element having a reverse direction structure asdescribed above, the organic light-emitting element may also be producedby sequentially depositing a cathode material, an organic material layerthereon, and an anode material on a substrate.

In the organic light-emitting element according to the presentinvention, the organic material layer may be produced with fewer layersby a solvent process other than a deposition method, for example, amethod, such as spin coating, dip coating, doctor blading, screenprinting, inkjet printing, a thermal transfer method or the like, byusing various polymer materials.

The organic material layer according to the present invention may have astacked structure in which the organic material layer includes a lightemitting layer, and one or more selected from a hole injection layer, ahole transporting layer, an electron transporting layer, and an electroninjection layer.

In the organic light-emitting element according to the presentinvention, a material capable of forming the hole injection layer ispreferably a material having a large work function such that theinjection of holes into the organic material layer may be normallyfacilitated. Specific examples of the hole injection material, which maybe used in the present invention, include a metal, such as vanadium,chromium, copper, zinc, and gold, or alloys thereof; a metal oxide, suchas zinc oxide, indium oxide, indium tin oxide (ITO), and indium zincoxide (IZO); a combination of metal and oxide, such as ZnO:Al orSnO₂:Sb; an electrically conductive polymer, such aspoly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDT),polypyrrole, and polyaniline, and the like, but are not limited thereto.

In the organic light-emitting element according to the presentinvention, a material capable of forming the electron injection layer ispreferably a material having a small work function such that electronsare easily injected into the organic material layer. Specific examplesof the electron injection material include a metal, such as magnesium,calcium, sodium, potassium, titanium, indium, yttrium, lithium,gadolinium, aluminum, silver, tin, and lead, or an alloys thereof; amulti-layer structured material, such as LiF/Al or LiO₂/Al, and thelike, and may use the same material as the hole injection material, butare not limited thereto.

In the organic light-emitting element according to the presentinvention, a material capable of forming the light emitting layer is amaterial capable of emitting light in a visible ray region by acceptingand recombining holes from the hole transporting layer and electronsfrom the electron transporting layer, respectively, and is preferably amaterial having high quantum efficiency for fluorescence orphosphorescence. Specific examples thereof include8-hydroxy-quinoline-aluminum complexes (Alq₃); carbazole-basedcompounds; dimerized styryl compounds; BAlq;10-hydroxybenzoquinoline-metal compounds; benzoxazole-based,benzthiazole-based and benzimidazole-based compounds;poly(p-phenylenevinylene) (PPV)-based polymers; spiro compounds;polyfluorene and rubrene; phosphorescence hostCBP[[4,4′-bis(9-carbazolyl)biphenyl]; and the like, but are not limitedthereto.

Further, the light emitting material may additionally include aphosphorescent dopant or a fluorescent dopant in order to improvefluorescent or phosphorescent characteristics. Specific examples of thephosphorescent dopant include Ir(ppy)₃(tris(2-phenylpyridine) iridium(III)), F₂Irpic(bis[2-(4,6,-di-fluorophenyl)pyridinato-N,C-2′]irridiumpicolinate) or the like. As the fluorescent dopant, those known in theart may be used.

In the organic light-emitting element according to the presentinvention, a material capable of forming the electron transporting layeris a material which may accept electrons from the electron injectionlayer well and transport the electrons to the light emitting layer, andis suitably a material having high mobility to electrons. Specificexamples thereof include Al complexes of 8-hydroxyquinoline; complexesincluding Alq₃; organic radical compounds; hydroxyflavone-metalcomplexes; and the like, but are not limited thereto.

The thickness of the organic material layer may be from 100 nm to 5 μm,but is not limited thereto. The organic material layer may be formed soas to cover a portion of the insulating layer on the above-describedfirst electrode, but is not limited thereto.

In the present invention, the substrate may be a glass substrate; aplastic substrate; a plastic film; a metal substrate; or a metal film.The thickness of the substrate may be from 10 μm to 10 mm, the thicknessof the lower electrode may be from 10 nm to 1 μm, but the thicknessesare not limited thereto.

As described above, in the organic light-emitting element according tothe present invention, the organic material layer and the secondelectrode have the same shape, and thus it is not necessary to replacethe mask during the process of depositing each of the organic materiallayer and the second electrode, thereby increasing the productivity ofthe organic light-emitting element. In addition, when the organiclight-emitting element is produced, it is possible to allowsimplification of vapor deposition equipment, thereby obtaining aneffect of reducing investment costs.

In particular, the organic light-emitting element according to thepresent invention may be used as a display element in various displaydevices and as a illumination device, but may be more preferably appliedfor illumination.

Yet another exemplary embodiment of the present invention provides amethod for producing an organic light-emitting element, including:forming a first electrode on a substrate; forming an organic materiallayer on the first electrode by using a mask; and forming a secondelectrode on the organic material layer, in which the organic materiallayer and the second electrode are formed by using the same mask.

The mask may be formed of a material selected from stainless steel, aninvar-based metal, titanium, a copper plate, and plastic. Here, anexample of plastic includes a PET film, but is not limited thereto. Thethickness of the mask may be from 5 μm to 5 mm, but is not limitedthereto.

The method for producing an organic light-emitting element according tothe present invention may further include using the mask to form theorganic material layer and the second electrode, and then washing themask. In the method for producing an organic light-emitting elementaccording to the present invention, the mask may be washed after themask is consecutively used in the forming of the organic material layerand the forming of the second electrode. On the contrary, in the methodfor producing an organic light-emitting element in the related art, amask for forming an organic material layer and a mask for forming asecond electrode are separately provided, and thus there is adisadvantage in that it is difficult to wash the mask for forming asecond electrode, and accordingly, the cost of replacing the mask isincreased.

The method for producing an organic light-emitting element according tothe present invention may further include forming an external terminalof the second electrode on the substrate. The external terminal of thesecond electrode may also be formed simultaneously with the firstelectrode or the same process as that of the first electrode.

In addition, the method for producing an organic light-emitting elementaccording to the present invention may further include forming aninsulating layer. The insulating layer may be an insulating layer forinsulating the first electrode with the external terminal of the secondelectrode. Furthermore, the insulating layer may be formed on at least aportion of the outermost part of a region, in which an organic materiallayer is to be formed, on the first electrode in order to prevent thefirst electrode and the second electrode from being shorted. Therefore,the forming of the insulating layer may be forming an insulating layerbetween the first electrode and the external terminal of the secondelectrode, or on at least a portion of the outermost part of a region inwhich the organic material layer is brought into contact with the firstelectrode.

Further, the method for producing an organic light-emitting elementaccording to the present invention may further include forming aconductive pattern on the external terminal of the second electrode.Specifically, the method may further include forming a conductivepattern on at least a portion of a region, in which the organic materiallayer and the second electrode are formed, on the top surface of theexternal terminal of the second electrode before the organic materiallayer and the second electrode are formed.

In the method for producing an organic light-emitting element accordingto the present invention, the second electrode is formed by using themask for forming an organic material layer without separately using themask for forming a second electrode, and thus a replacement line forreplacing the two kinds of masks may be removed and a mask charging partin the related art may be removed, thereby providing simplification ofequipment.

In the case of the method in the related art, which separately usesmasks in the forming of the organic material layer and the forming ofthe second electrode, a time for arranging the substrate and the masksis additionally required, but in the method for producing an organiclight-emitting element according to the present invention, the two stepsmay be performed by using one mask, thereby reducing the process timethan in the related art.

In addition, in the case of the method in the related art, whichseparately uses masks in the forming of the organic material layer andthe forming of the second electrode, an additional module for theproduction device, such as a separate chamber for each mask, areplacement device unit of a mask, a washing device of the mask and thelike, needs to be provided, but in the method for producing an organiclight-emitting element according to the present invention, the formingof the organic material layer and the forming of the second electrodemay be performed by using one mask, and thus the additional module isnot required, thereby simplifying the production device of the organiclight-emitting element.

Furthermore, it is easy to wash the mask consecutively used in theforming of the organic material layer and the forming of the secondelectrode, and thus the mask may be used for a prolonged time and thecosts of replacing the mask may be reduced. Further, according to thepresent invention, it is possible to allow simplification of equipment,reduce the costs of replacing the mask, and reduce the process time.

The invention claimed is:
 1. An organic light-emitting element having astructure in which a first electrode, an organic material layer, asecond electrode are sequentially stacked on a substrate, an externalterminal of the second electrode provided to be insulated from the firstelectrode on the substrate, and a conductive pattern that electricallyconnects the second electrode with the external terminal of the secondelectrode, wherein a shape of the second electrode is the same as thatof the organic material layer, wherein an upper side area of the secondelectrode is the same as that of the organic material layer or has asize difference from that of the organic material layer in a rangewithin 10%, wherein the conductive pattern has a structure in which theconductive pattern passes through the organic material layer from a topsurface of the external terminal of the second electrode to be broughtinto contact with the second electrode or pass through the secondelectrode, and the conductive pattern is disposed inside the organicmaterial layer such that it is completely surrounded by the organicmaterial layer in a plan view, and wherein the first electrode and theexternal terminal of the second electrode are directly provided on thesame surface of the substrate.
 2. The organic light-emitting element ofclaim 1, wherein the upper side area of the second electrode is the sameas that of the organic material layer.
 3. The organic light-emittingelement of claim 1, wherein a maximum angle between a side surface shapeof the conductive pattern and the top surface of the external terminalof the second electrode is 40° or more.
 4. The organic light-emittingelement of claim 1, wherein a height of the conductive pattern is twiceor more than a thickness of the organic material layer.
 5. The organiclight-emitting element of claim 1, wherein an insulating layer isprovided between the first electrode and the external terminal of thesecond electrode.
 6. The organic light-emitting element of claim 1,wherein an insulating layer is additionally provided on at least aportion of an outermost part of a region in which the organic materiallayer is brought into contact with the first electrode.
 7. The organiclight-emitting element of claim 1 is for illumination.